[m-rev.] diff: speed up cache hits in write_deps_file.m

[Zoltan Somogyi]

This does not need review.

Zoltan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Log.wdf2
Type: application/octet-stream
Size: 470 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20230909/daf8582a/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DIFF.wdf2
Type: application/octet-stream
Size: 3279 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20230909/daf8582a/attachment-0001.obj>